Expansible pulley.



c. F. BENJAMIN. BXPANSIBLE PULLEY.

APPLICATION FILED OCT.- 16, 1908.

912,442.- Patented Feb. 16, 1909.

3 SHEETS-SHEET 1.

anuenl'ot Ghrvnce f' 0. F. BENJAMIN. EXPANSIBLB PULLEY. APPLICATION FILED OUT. 16, 1908.

Patented Fb. 16,-'190'9.

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CLARENCE FRANKLIN BENJAMIN, Ola PHILADELPHIA, PENNSYLVANIA.

EXPANSIBLE PULLEY.

Specification of Letters Patent.

Patented Feb. 16, 1909.

Application filed October 16, 1908. Serial No. 457,979.

To all whom it may concern:

Be it known that I, CLARENCE F. BENJA- MIN, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Expansible Pulleys, of which the following is a specification.

My invention relates to improvements in expansible pulleys, and more particularly to improvements upon the structure set forth in Letters Patent No. 896,267, granted to me August 18, 1908, an obj ect of the invention being to provide improved mounting and operating mechanism for the radially movable segmental rim sections of the pulley, so as to absolutely preclude any possibility of the rim sections being moved by the centrifugal action of the revolving pulley.

A further object is to provide mechanism of this character with improved wedges, which are so connected with the radially movable rim sections that the movement of the wedges in one direction will force the sections outward, and the reverse movement of the wedges will draw the sections inward without the employment of springs of any kind.

A further object is to provide improved means for moving each of a circular series of wedges in turn, so as to gradually expand the pulley.

A further object is to provide improved mechanism for compelling the simultaneous movement of the wedges when contracting the pulley.

With these and other objects in view the invention consists in certain novel features of construction, combinations and arrangements of parts as will be more fully hereinafter described and pointed out in the claims.

In the accompanying drawings Figure 1, is a view partly in section and partly in elevation illustrating my improvements. Fig. 2, is a view in section on line w::r, of Fig. 1. Fig. 3, is a view in section on line 3 g of Fig. 1. Fig. 4, is a view in end elevation of the adjusting collar and its cooperating parts. Fig. 5, is a fragmental view in longitudinal section on line ez of Fig. A. Fig. 6, is a fragmental section on line aa of Fig. 1. Fig. 7, is a perspective View of the sliding sleeve.

Fig. 8, is a detail perspective viewv of one of the wedges, and Fig. 9, is a similar view of a slightly modified construction of wedge.

1 represents a shaft and 2 a sleeve keyed to said shaft and having integral disks 33 at its ends forming a wheel. The spokes A of these disks 33 are provided with radial grooves 5 in which are mounted tongues or tenons 6 at the respective edges of radially movable arms 7, the latter at their outer ends, carrying the segmental pulley rim sections 8. It will be seen that when the pulley is in its contracted form the segmental sections are substantially flush with the edges of the disks 3, and when expanded will be forced outward beyond the edges of the disks 3 as will be hereinafter explained.

The innerends of the arms 7 are bifurcated as clearly shown at 9 in Fig. 2. The inner edges of all of the arms 7 are inclined or beveled at an angle substantially as shown in Fig. 1, and the bifurcated inner ends of these arms 7 are provided on their inner faces with opposed flanges or tongues 10 located in grooves 11 in the opposite faces of wedges 12. The straight inner edges of all of the wedges are mounted to slide upon the sleeve 2, and the spokes 4: are made with openings 13 and 14 respectively to permit free sliding movement of the wedges through the spokes and one series of openings 14:, in one of the sets of spokes at, are long enough to receive enlargements 15 on the outer portion of the wedges. The enlargements 15 have their outer edges disposed parallel with the inner edges of the wedges, and the openings 1% are just long enough to accommodate the enlarged portion of the wedges and absolutely prevent any movement of the wedges away from sleeve 2. As the wedges and the arms 7 are locked by the groove and flange connection above described, the one member cannot move without moving the other, and hence no amount of centrifugal force could possibly draw the segmental sections outward as they are securely held against such accidental movement by the shape of the wedges above described. At the larger ends of the wedges, which I will term the forcollar is moved tbward the pulley, will tend to throw the ring 27 at a tangent, and will hence first cause the wedges nearest the roller to be moved first, and as the pulley revolves the several wedges will be forced inward in turn.

The operation of my improvements is as follows: With the parts as shown in Figs. 1 and 2, the pulley is contracted. By swinging the lever 26 so as to move the collar 25 to the left, the roller 28 will press against ring 27 and force all of the wedges in turn to the left, and due to the cam engagement of the arm 7 with the wedges 12, the arms and their segmental rim portions will be forced outward to expand the pulley. When the wedges 12 are moved in the direction above described, the lugs 19 on the arms 16 of the Wedges, ,due to their engagement with the spring 20, will compel the sleeve 18 and the casing 23 to follow the wedges during v *A w .LALwVAALl/LUll v-L ULLV \JLJ-(l/L ll/UUUJ. U- scribed, the combination with a support and a series of radially movable pulley sections thereon, of a series of longitudinally movable wedges having cam engagement with said sections, and enlargements on said wedges having their outer edges constructed to engage the section supports to prevent the accidental radial movement of the sections.

2. In a mechanism of the character described, the combination with a shaft, a sleeve secured thereon and disks at the ends of said sleeve having radially disposed grooves in their opposed faces, radially movable arms, tenons on the arms located in the grooves, segmental rim sections on said arms, said arms having bifurcated inner ends, a wedge for each arm having inclined grooves on its opposite sides, tongues in the bifurcated ends of the arms located in said grooves, means for movlng the wedges, and enlargements on the wedges havmg their outer edges parallel with the inner edges of the wedges and located in slots in one of said disks.

3. In a mechanism of the character described, the combination with a series of radially movable pulley sections, and a series of longitudinally movable wedges to move said pulley sections, a sliding sleeve having longitudinal grooves in its periphery, arms or extensions on said wedges located in the grooves, inwardly projecting lugs on the free ends of the arms, a spring ring at one end of the sleeve and engaging behind the lugs of the arms, and means for moving said sleeve in one direction to compel movement of the wedges to contract the pulley.

a. In a mechanism of the character described, the combination with a series of radially movable pulley sections, and a series of longitudinally movable wedges to move said pulley sections, a sliding sleeve having longitudinal grooves in its periphery, arms or extensions on said wedges located in the grooves, inwardly projecting lugs on the free ends of the arms, a spring ring at one end of the sleeve and engaging behind the lugs 01" the arms, a casing inclosing said sleeve and arms, a split collar around said casing, a flange at one end of the casing overlapping the edge of the collar, a ring on the shaft between said collar and the main portion of the wedges, and a roller carried by said collar in engagement with the said ring.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CLARENCE FRANKLIN BENJAMIN.

Witnesses:

R. H. KRENKEL, J. A. L. MULHALL. 

